I can confirm that on my (6-year old) Toshiba, I had no data on Saturday, Feb 23, 2013. However, since I would typically have had a week or so of advance data, that would mean that the last data update was at least as far back as Feb 16th. So it looks like the OTA TV guide might be gone...
I still have data on my (newer) Sony, however, which is able to get listings from the internet (not just OTA). So if your TV happens to be internet-capable, you could try changing its settings to get the TV guide from an online source. If not, it might be time to hook up an internet-capable device to your TV, so at least you can check out the listings on Zap2it.com
I live just North of Toronto, by the way, and had been getting TVGOS data from CFTO with no problem for years. I had also heard recently that Rovi would be phasing out the OTA data over several months...looks like they got to CFTO.
Edited by fbruce - 2/24/13 at 12:07am